"There is the lunch-bell; but I shall be very happy to explain the matter more fully later in the day, Miss Woolridge, unless you prefer that Louis should do it," suggested Scott.
"I doubt if I could do it, and I should be glad to listen to the explanation," replied Louis, as they descended to the main cabin; for the new third officer was permitted to retain his place at the table as well as his state-room.
The commander had suggested that there was likely to be some change of cabin arrangements; for it was not in accordance with his ideas of right that the third officer should be admitted to the table, while the first and second were excluded; and Louis was very desirous that his friend Scott should remain in the cabin. The repasts on board the steamer were social occasions, and the party often sat quite an hour at the table, as at the present luncheon. But as soon as the company left their places, Louis and Miss Blanche followed the third officer to the promenade deck, to hear the desired explanation of sea-time.
"Of course you know how the longitude of the ship is obtained, Miss Woolridge?" the young officer began.
"Papa explained it to me once, but I could not understand it," replied the fair maiden.
"Then we will explain that first. One of the great circles extending through the poles is called the prime meridian; and any one may be selected, though that of Greenwich has been almost universally adopted. This place is near London. From this prime meridian longitude is calculated, which means that any given locality is so many degrees east or west of it. Sandy Hook is in longitude 74°, or it is that number of degrees west of Greenwich. Aden is in 45° east longitude."
"Then you find how many miles it is by multiplying the number of degrees by 69," suggested Miss Blanche.
"You have forgotten about knots, or sea-miles," said Louis.
"So I have! I should have said multiply by 60," added the young lady.
"That would not do it any better," replied Scott.